Proteins in Complement, Immune, and Clotting Cascades and their Role in Preterm Births

Preterm birth (PTB) (< 37 completed weeks gestation) is a pathological outcome of pregnancy and its associated complications are the leading global cause of death in children younger than 5 years of age. Babies born prematurely have an elevated risk for short- and long-term adverse effects of medical and neurodevelopmental sequelae. Substantial evidence suggests that multiple sets of symptoms are allied with PTB etiology, and the exact mechanism cannot be recognized. Notably, various proteins, especially (i) complement cascade; (ii) immune system; and (iii) clotting cascade, have become attractive research targets that are associated with PTB. Further, a small imbalance of these proteins in maternal or foetal circulation could serve as a marker/precursor in a series of events that lead to PTBs. Thus, the present review lightens the basic description of the circulating proteins, their role in PTB, and current concepts for future development. Further, deepening the research on these proteins will lead to a better understanding of PTB etiology and alleviate scientists' confidence in the early identification of PTB mechanisms and biological markers.